Is a signature scheme using a hash considered a hybrid cryptosystem?

In Wikipedia there is a page on hybrid cryptosystems. However, although cryptography contains a lot more than just encryption, only hybrid encryption using key encapsulation and data encapsulation is discussed.

So my simple question is: should I consider a signature scheme using a hash a hybrid cryptosystem? Or is the term not that well defined and is it up to the entity that uses the term?

• Isn't the word cryptosystem only used for encryption? – CodesInChaos Jan 11 '18 at 0:01
• Hmm, it is according to Wikipedia. Must be something from the olden days maybe. I was thinking that it is just several algorithm tossed together to create any kind of system. Could be the answer... – Maarten Bodewes Jan 11 '18 at 0:04

What I didn't directly see is that a hybrid cryptosystem is not the same thing as hybrid cryptography. A cryptosystem is commonly targeting encryption: it exists of a key generation function $\operatorname{Gen}$, an encryption function $\operatorname{Enc}$ of course a decryption function $\operatorname{Dec}$.
So although signature generation could probably be called hybrid cryptography, it commonly isn't a hybrid cryptosystem because it lacks the $\operatorname{Enc}$ and $\operatorname{Dec}$ function.